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Breviscapine is one of the extracts of several flavonoids of Erigeron breviscapus. Scutellarin is the main active component of breviscapine, and the qualitative or quantitative criteria as well. Scutellarin and its analogs share a similar skeleton of the flavonoids. Breviscapine has been widely used in the treatment of cerebral infarction and its sequelae, cerebral thrombus, coronary heart disease (CHD), and angina pectoris. Breviscapine has a broad spectrum of pharmacological activities, such as increasing blood flow, improving microcirculation, dilating blood vessels, decreasing blood viscosity, promoting fibrinolysis, inhibiting platelet aggregation, and thrombosis formation, etc. In addition, breviscapine and its analogs have significant value for drug research and development because of the superiority of those significant bioactivities. Furthermore, an increasing number of pharmacokinetic studies have explored the mechanism of scutellarin and its analogs. To provide a comprehensive understanding of the current research on breviscapine, scutellarin, and the analogs, the structural features, distribution situation, preparation method, content determination method, clinical applications, pharmacological action as well as pharmacokinetics are summarized in the present review.

In this research, twenty aromatic and branched aliphatic polyketides, including seven previously undescribed butenolide derivatives, piterriones A–G and one known analogue, along with twelve known altenusin derivatives, were isolated from the isopod-associated fungus Pidoplitchkoviella terricola. Their structures were elucidated by analysis of NMR (1D and 2D) and mass spectrometry data, and their absolute configurations were determined by Mosher's method, microscale derivatization, and comparison of their specific rotations and ECD spectra. Dihydroaltenuene B exhibited mushroom tyrosinase inhibitory activity with an IC50 value of 38.33 ± 1.59 μM, which was comparable to that of the positive control, kojic acid (IC50 = 39.72 ± 1.34 μM). A molecular-docking study disclosed the hydrogen bonding interactions between the 3-OH and 4′-OH of dihydroaltenuene B and the His244, Met280 and Gly281 residues of tyrosinase.

Uncontrolled bleeding is the main cause of mortality from trauma. Collagen has been developed as an important hemostatic material due to its platelet affinity function. A bath sponge skeleton is rich in collagen, also known as spongin. To understand the hemostatic effect of spongin, spongin materials, SX, SFM and SR were prepared from the bath sponge Spongia officinalis, and hemostatic experiments were performed. The SX, SFM and SR were significantly better than the positive control, type I collagen, in shortening the whole blood clotting time in vitro and hemostasis upon rat tail amputation. In a hemostatic experiment of rabbit common carotid artery injury, the hemostatic time and 3 h survival rate of the SFM group were 3.00 ± 1.53 min and 100%, respectively, which are significantly better than those of the commercial hemostat CELOX-A (10.33 ± 1.37 min and 67%, respectively). Additionally, the SFM showed good coagulation effects in platelet-deficient blood and defibrinated blood, while also showing good biocompatibility. Through a variety of tests, we speculated that the hemostatic activity of the SFM is mainly caused by its hyperabsorbency, high affinity to platelets and high effective concentration. Overall, the SFM and spongin derivates could be potential hemostatic agents for uncontrolled bleeding and hemorrhagic diseases caused by deficiency or dysfunction of coagulation factors.

Eleven new cyathane diterpenoids, designated cyafricanins A–K (1−11), were isolated from the culture broth of the baisidiomycete Cyathus africanus (Nidulariaceae, Bird's nest fungi). Their structures were elucidated by comprehensive analysis of their NMR and HRESIMS data. Cyafricanins A (1) was found to possess an unusual 3,4-seco‑carbon skeleton. All compounds were evaluated for their neurotrophic activity in PC-12 cells and anti-neuroinflammatory activity in BV2 microglia cells. All of the diterpenoids showed nerve growth factor induced neurite outgrowth-promoting activity at concentration of 20 μM. Among them, cyafricanin B (2) and cyafricanin G (7) exhibited promising neurotrophic activity, and cyafricanin A (1) showed strong inhibitory effects on both inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression. Furthermore, molecular docking studies revealed that cyafricanin A (1) showed strong interactions with the iNOs protein in the active cavity.

CDK4/6 were attractive chemotherapeutic targets for the treatment of malignant tumors, CDK4/6 selective inhibitors have made outstanding contributions in the treatment of breast cancer. However, these inhibitors share a single skeleton of N-(pyridin-2-yl) pyrimidin-2-amine which cannot overcome the side effects in clinical application. In our previous study, an N'- acetylpyrrolidine-1-carbohydrazide was hit as the initial fragment by analyzing the active site characteristics of CDK6. Two series of N-(pyridin-3-yl) proline were obtained by fragment growth method. The QSAR study was carried out according to the in vitro activities data against CDK4/6, and two compounds 7c and 7p with potent inhibitory activities were found to interact with CDK4 in different binding conformation. They showed potential inhibition of cell proliferation against the breast cancer cell, and 7c exhibited promised anti-breast cancer effect in vivo.

Two new 2-carboxymethyl-3-hexyl-maleic anhydride derivatives, arthrianhydride A (1) and B (2), along with three known compounds 3-5, were isolated from the fermentation broth of a grasshopper-associated fungus Arthrinium sp. NF2410. The structures of new compounds 1 and 2 were determined based on the analysis of the HR-ESI-MS and NMR spectroscopic data. Furthermore, compounds 1 and 2 were evaluated on inhibitory activity against the enzyme SHP2 and both of them showed moderate inhibitory activity against SHP2.

Cyclin-dependent kinase 2 (CDK2) is the family of Ser/Thr protein kinases that has emerged as a highly selective with low toxic cancer therapy target. A multistage virtual screening method combined by SVM, protein-ligand interaction fingerprints (PLIF) pharmacophore and docking was utilised for screening the CDK2 inhibitors. The evaluation of the validation set indicated that this method can be used to screen large chemical databases because it has a high hit-rate and enrichment factor (80.1% and 332.83 respectively). Six compounds were screened out from NCI, Enamine and Pubchem database. After molecular dynamics and binding free energy calculation, two compounds had great potential as novel CDK2 inhibitors and they also showed selective inhibition against CDK2 in the kinase activity assay.

The Inhibition of cellular nucleotide metabolism to promote apoptosis is a key principle of cancer therapy. Thymidylate synthase (TS) is a key rate-limiting enzyme in the initiation of DNA synthesis in cell. Here, we presented two types of thymidylate synthase inhibitors, and, the key pharmacological properties of these two types of thymidylate synthase inhibitor were extracted and combined to design new compounds with inhibitory activity. Therefore, two series of 42 new compounds with the common biological effect of promoting apoptosis are designed and synthesized by combination principle. Most of the compounds had good anti-proliferative activity on A549, OVCAR-3, SGC7901 and MDA-MB-231 cells. The IC50 of compound 10l on A549 cells was 1.26 μM, which was better than that of pemetrexed (PTX, IC50 = 3.31 μM), furthermore, the selection index of compound 10l was higher than PTX. Flow cytometry analysis showed that compound 10l (the apoptosis rate is 39.4%) could induce A549 cell apoptosis and effectively inhibit tumor cell proliferation. Further western blot analysis showed that compound 10l could induce intrinsic apoptosis by activating caspase-3, increasing expression of cleaved caspase-3 and reducing the ratio of bcl-2/bax. All of this makes compound 10l to be a promising compound in future animal tumor models.

Backgound: Vascular endothelial growth factor receptor-2 (VEGFR-2) plays a crucial role in the process of cancer angiogenesis. Type I inhibitors constitute the major ATP-competitive inhibitors and recognize mainly the active conformation of VEGFR-2. Meanwhile, type II inhibitors recognize the inactive DFG (Asp- Phe-Gly)-out conformation of VEGFR-2, which was a more promising approach for drug intervention. Methods: According to the lead compound of uracil skeleton, being screened out by structure-based virtual screening, a series of uracil derivatives were designed and synthesized. Results: The inhibitory activities were investigated against VEGFR-2 kinase in vitro. The results turned out that series A performed moderate inhibitory activities, especially compound A4 exhibited the most potent inhibitory activity (IC50=0.029 µM). Conclusion: The lead compound was screened out by structure-based pharmacophore models, then two series of uracil derivatives were synthesized according to it and evaluated for their inhibitory activities against VEGFR-2. In this study, not only a potential inhibitor has been discovered, it also demonstrates the feasibility of structure-based virtual screening method for drug discovery.

Two new carotane-type sesquiterpenes named trichocaranes E (1) and F (2), along with two known ones CAF-603 (3) and trichocarane C (4), were isolated from cultures of the insect pathogenic fungus Isaria fumosorosea. Their structures and relative configurations were elucidated by extensive spectroscopic analysis and X-ray crystallography. Compounds 1-3 showed potent cytotoxic activities against six tumor cell lines MDA, MCF-7, SKOV-3, Hela, A549, HepG2 with IC

A series of homoerythrina alkaloid derivatives containing a 1,2,3-triazole moiety as PARP-1 inhibitors were designed and synthesized. And their anti-proliferative activity was further evaluated. Compound 10n had excellent activity to inhibit proliferation of A549 cells (IC50 = 1.89 μM), which was higher than harringtonine (IC50 = 10.55 μM), pemetrexed (IC50 = 3.39 μM), and rucaparib (IC50 = 4.91 μM). Furthermore, the selectivity index of compound 10n was higher than rucaparib and pemetrexed for lung cancer cells. Flow cytometry analysis showed that compound 10n significantly arrested the cell cycle in the S phase, then induced apoptosis of A549 cells (apoptosis rate is 46%), which effectively inhibited cell proliferation. Simultaneously, western blot analysis revealed that compound 10n could prevent the biosynthesis of PAR. Further analysis results revealed that compound 10n could inhibit the expression of cyclin A, down-regulate the expression of bcl-2/bax, activate caspase-3, and ultimately induce apoptosis of A549 cells. All the results indicated that compound 10n had potential research value as a novel PARP-1 inhibitor in antitumor, and it provided a new reference for further development of PARP-1 inhibitors.

Marine animals and plants provide abundant secondary metabolites with antitumor activity. Itampolin A is a brominated natural tyrosine secondary metabolite that is isolated from the sponge Iotrochota purpurea. Recently, we have achieved the first total synthesis of this brominated tyrosine secondary metabolite, which was found to be a potent p38α inhibitor exhibiting anticancer effects. A fragment-based drug design (FBDD) was carried out to optimize itampolin A. Forty-five brominated tyrosine derivatives were synthesized with interesting biological activities. Then, a QSAR study was carried out to explore the structural determinants responsible for the activity of brominated tyrosine skeleton p38α inhibitors. The lead compound was optimized by a FBDD method, then three series of brominated tyrosine derivatives were synthesized and evaluated for their inhibitory activities against p38α and tumor cells. Compound 6o (IC50 = 0.66 μM) exhibited significant antitumor activity against non-small cell lung A549 cells (A549). This also demonstrated the feasibility of the FBDD method of structural optimization.

Transition metal dichalcogenide (TMD) nanosheets have evoked enormous research enthusiasm and have shown increased potentials in the biomedical field. However, a great challenge lies in high-throughput, large-scale, and eco-friendly preparation of TMD nanosheet dispersions with high quality. Herein, we report a universal polyphenol-assisted strategy to facilely exfoliate various TMDs into monolayer or few-layer nanosheets. By optimizing the exfoliation condition of molybdenum disulfide (MoS

To investigate structurally novel and anti-neuroinflammatory natural compounds from marine-derived microorganisms, the secondary metabolites of Aspergillus terreus Y10, a fungus separated from the sediment of the coast in the South China Sea, were studied. Three new compounds (2–4), with novel open-ring butenolide skeletons, were isolated from the ethyl acetate extract of the culture medium. In addition, a typical new butenolide, asperteretal F (1), was found to dose-dependently inhibit tumor necrosis factor (TNF-α) generation with an IC50 of 7.6 μg/mL. The present study shows the existence of open-ring butenolides, and suggests that butenolides such as asperteretal F (1) are a promising new anti-neuroinflammatroy candidate for neurodegenerative diseases.

The molecular chaperone heat shock protein 90 (Hsp90) is a promising target for cancer therapy. Natural product aconitine is a potential Hsp90 inhibitor reported in our previous work. In this study, we designed and synthesized a series of 2-((1-phenyl-1H-1,2,3-triazol-4-yl)methyl)-2-azabicyclo[3.2.1]octan-3-one derivatives as potent Hsp90 inhibitors by simplifying and modifying aconitine scaffold. Among these compounds, 14t exhibited an excellent antiproliferative activity against LoVo cells with an IC50 value of 0.02 μM and a significant Hsp90α inhibitory activity with an IC50 value of 0.71 nM. Molecular docking studies provided a rational binding model of 14t in complex with Hsp90α. The following cell cycle and apoptosis assays revealed that compound 14t could arrest cell cycle at G1/S phase and induce cell apoptosis via up-regulation of bax and cleaved-caspase 3 protein expressions while inhibiting the expressions of bcl-2. Moreover, 14t could inhibit cell migration in LoVo and SW620 cell lines. Consistent with in vitro results, 14t significantly repressed tumor growth in the SW620 xenograft mouse model.

Hederagenin is a naturally occurring pentacyclic triterpenoids compound with multiple pharmacological activities. We recently showed that H6, a synthetic derivative of hederagenin, could enhance the anticancer activity of paclitaxel in drug-resistant cells in vitro and in vivo, but showed poor solubility. With the aim of improving the drug resistant reversal activity of H6, here we designed and synthesized a series of novel H6 analogues. Our results showed that compound 10 at the concentration of 5 μM significantly enhanced the cytotoxicity of paclitaxel to drug-resistant KBV cells and sensitized cells to paclitaxel in arresting cells in G2/M phase and inducing apoptosis. We found that compound 10 might block the drug efflux of P-gp via stimulating P-gp ATPase activity. Importantly, compound 10 enhanced the efficacy of paclitaxel against KBV cancer cell-derived xenograft tumors. Finally, we summarized a preliminary structure-activity relationship of hederagenin by the drug resistant reversal activity of H6 analogues in vitro and compound 10 and H6 in vivo. This study highlights the importance of nitrogen-containing derivatives of hederagenin C-28 in the development of novel drug resistance reversal agents.

A series of new sinomenine derivatives were designed, synthesized, and evaluated in tumor inhibitory activity, such as human triple negative breast cancer cell line (MDA-MB-231), glioma cell line (A172), human lung cancer cell line (A549), human colon cancer cell line (HCT-8). The modifications were carried out on rings A and C of the sinomenine by esterificating on phenolic hydroxyl with good yields. The highlight of this work was that the synthetic procedures were concise and sinomenine derivatives demonstrated promising antitumor activities.

Six new highly oxygenated polycyclic cyathane-xylosides, named striatoids A-F (1-6), were isolated from the cultures of the basidiomycete Cyathus striatus. Their structures were established by comprehensive spectroscopic analysis including 2D NMR (HMBC, HSQC, ROESY, (1)H-(1)H-COSY) and HRESIMS experiments. Compounds 2 and 3 possess an unusual 15,4'-ether ring system. The isolated compounds dose-dependently enhanced nerve growth factor (NGF)-mediated neurite outgrowth in rat pheochromocytoma (PC-12) cells.

Ten new polyoxygenated cyathane diterpenoids, named neocyathins A–J (1–10), together with four known diterpenes (11–14), were isolated from the liquid culture of the medicinal basidiomycete fungus Cyathus africanus. The structures and configurations of these new compounds were elucidated through comprehensive spectroscopic analyses including 1D NMR, 2D NMR (HSQC, HMBC, NOESY) and HRESIMS, and electronic circular dichroism (ECD) data. Neuroinflammation is implicated in the pathogenesis of various neurodegenerative diseases, such as Alzheimers’ disease (AD). All isolated compounds were evaluated for the potential anti-neuroinflammatory activities in BV2 microglia cells. Several compounds showed differential effects on the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in lipopolysaccharide (LPS)-stimulated and Aβ1–42-treated mouse microglia cell line BV-2. Molecular docking revealed that bioactive compounds (e.g., 11) could interact with iNOS protein other than COX-2 protein. Collectively, our results suggested that this class of cyathane diterpenoids might serve as important lead compounds for drug discovery against neuroinflammation in AD.

Novel N-substituted tetrahydro-β-carboline imidazolium salt derivatives proved to have potent antitumor activity in past research. The Topomer CoMFA and CoMSIA function in Sybyl-X 2.0 software was applied for the identification of important features of N-substituted tetrahydro-β-carboline-imidazolium salt derivative moieties. In the case of Topomer CoMFA, all the compounds were split into two fragments which were used to generate a 3D invariant representation, the statistical results of the Topomer CoMFA model: q2 value of 0.700; r2 value of 0.954; with 5 optimum components. The database alignment was utilized for building the CoMSIA model, and the CoMSIA model had q2 and r2 values of 0.615 and 0.897, with 4 optimum components. Target fishing of the PharmMapper platform was utilised for finding potential targets, the human mitogen-activated protein kinase 1 (MEK-1) was found to be the primary potential target for the three compounds with the fit scores of 6.288, 5.741, and 6.721. The molecular docking technique of MOE 2015 was carried out to identify the interactions of amino acids surrounding the ligand, and correlating QASR contour maps were used to identify structural requirements of N-substituted tetrahydro-β-carboline imidazolium salt moieties. Molecular dynamics and simulation studies proved that the target protein was stable for 0.8–5 ns. The pivotal moieties of N-substituted tetrahydro-β-carboline imidazolium salt derivatives and its potential targets were verified by the QASR study, PharmMapper, and the molecular docking study which would be helpful to design novel MEK-1 inhibitors for anticancer drugs.

Apoferritin caged gold nanoparticles (AuNPs) were assembled into flower-like structures by precise base pairing of the attached DNA molecules. The key step was to use the eight hydrophilic channels through the apoferritin to control the exact number and locations of the DNA molecules that grafted onto the caged AuNP.

Nine known metabolites, 6,8,1'-tri-O-methyl averantin (1), 6,8-di-O-methyl averufnin (2), 6,8-di-O-methyl averufanin (3), aversin (4), 1,3-dihydroxy-6,8-dimethoxy-9,10-anthraquinone (5), 6,8-di-O-methylnidurufin (6), 6,8-di-O-methyl versiconol (7), 5-methyoxysterigmatocystin (8) and (S)-ornidazole (9), were isolated from the extracts of Penicillium purpurogenum, and their structures were elucidated by using spectroscopic methods. The brine shrimp toxicity, anti-phytopathogenic and phytotoxic effects of these compounds were evaluated. Among them, compounds 1 and 8 exhibited the strongest toxicity against brine shrimp (Artemia salina), with lethality rates of 100% at a low concentration of 10 μM, comparable to the positive control toosendanin. Compounds 1, 4 and 7 moderately inhibited the growth of Botrytis cinerea. Moreover, 4 displayed moderate antifungal effects on Gibberella saubinettii. In addition, compounds 6, 7 and 9 produced the phytotoxic effects on radish seedlings at 100 μM. This is the first report on the isolation of these metabolites from this organism.

A simple 4-aniline boron-dipyrromethene (BODIPY) dye (1) was developed as a highly sensitive acidic pH fluorescent probe excitable with visible light based on a photoinduced electron transfer (PeT) mechanism. The pH titration indicates that the fluorescence intensity increases more than 500-fold within the pH range of 4.12-1.42 with a pKa value of 3.24 in methanol-water (1 : 1, v/v) solution, which is valuable for studying strongly acidic conditions. Density functional theory (DFT) calculations reproduce the fluorescence off-on behavior. 1 has also been used as a fluorescent chemosensor for the visual detection of dissolved carbon dioxide (CO2) gas. The underlying mechanism of the sensing process is rationalized. This probe can be recovered by bubbling nitrogen (N2) gas into CO2-treated solutions for over 10 cycles. In addition, two logic gates (OR and INH) have been achieved at the molecular level by changing the initial states of system 1 and chemical inputs.

The syntheses, structure-activity relationships (SARs), and biological activities of tetrahydroquinoline-based tricyclic amines as 5-HT

Four new polyisoprenylated benzoylphloroglucinol derivatives, hyperscabrones J–M (1–4), were isolated from the air-dried aerial parts of Hypericum scabrum. Their structures were elucidated by spectroscopic methods and were subsequently confirmed by comparing with data of known compounds. The absolute configuration of the bicyclo[3.3.1]nonane-2,4,9-trione core was defined by the experimental and calculated electronic circular dichroism (ECD) spectra. The evaluation of their hepatoprotective activities against paracetamol-induced HepG2 cell damage showed that compounds 2 and 4 exhibited significant hepatoprotection at 10 μM.

Twenty-four metabolites 1–24 were isolated from the fermentation broth of Streptomyces xanthophaeus. Their structures were elucidated on the basis of spectroscopic analysis and by comparison of their NMR data with literature data reported. Daidzein (1), genistein (2) and gliricidin (3) inhibited α-glucosidase in vitro with IC50 values of 174.2, 36.1 and 47.4 μM, respectively, more potent than the positive control, acarbose. Docking study revealed that the amino acid residue Thr 215 is the essential binding site for active ligands 2. In addition, the phytotoxic effects of all compounds were assayed on radish seedlings, five of which, 3, 8, 13, 15 and 18, inhibited the growth of radish (Raphanus sativus) seedlings with inhibitory rates of >60% at a concentration of 100 ppm, which was comparable or superior to the positive control glyphosate. This is the first report of the phytotoxicity of the compounds.

Breast cancer cells express ABCG2 transporters, which mediate multidrug resistance. Discovering a novel compound that can suppress ABCG2 expression and restore drug sensitivity could be the key to improving breast cancer therapeutics. In the current work, one new nor-neolignan, asperjinone (1), as well as 12 other known compounds, was isolated from Aspergillus terreus. The structure of the new isolate was determined by spectroscopic methods. Among these isolates, terrein (2) displayed strong cytotoxicity against breast cancer MCF-7 cells. Treatment with terrein (2) significantly suppressed growth of ABCG2-expressing breast cancer cells. This suppressive effect was achieved by inducing apoptosis via activating the caspase-7 pathway and inhibiting the Akt signaling pathway, which led to a decrease in ABCG2-expressing cells and a reduction in the side-population phenotype.

The investigation of chemical constituents from the branches of Calophyllum inophyllum Linn led to the isolation of a new prenylated xanthone, named caloxanthone Q (1), together with three known compounds, 2-deprenylrheediaxanthone B (2), jacareubin (3), and 6-deoxyjacareubin (4). Their structures were completely elucidated on the basis of spectroscopic methods (UV, IR, HR-ESI-MS, 1D NMR, and 2D NMR).

The present study was conducted to investigate whether safflor yellow B (SYB) had a protective effect on cerebral ischemic injury and to determine the possible mechanisms in vivo and in vitro. In vivo, Male Wistar-Kyoto (WKY) rats were used to make the model of middle cerebral artery occlusion (MCAO). The behavioral test was used to measure neurological deficit scores for evaluation of the ischemic damage of brain. The infarction area of brain was assessed in brain slices stained with 2% solution of 2,3,5-triphenyl tetrazolium chloride (TTC). Spectrophotometric assay was used to determine the activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx), contents of malondialdehyde (MDA) and adenosine triphosphate (ATP) of the brain. Furthermore, the respiratory control ratio (RCR = state 3/state 4) was assessed in the brain mitochondria. In vitro, the effect of SYB was tested in cultured fetal cortical cells exposed to glutamate to identify its neuroprotection against neurons damage. The results in vivo showed that SYB at doses of 3.0 and 6.0 mg kg(-1) markedly decreased the neurological deficit scores and the infarction area in MCAO rats. At the same time, SYB significantly improved mitochondrial energy metabolism, decreased MDA content, and increased SOD and GPx activities in ischemic brain. The results in vitro showed that SYB remarkably inhibited neuron damage induced by glutamate in cultured fetal cortical cells. These suggest that SYB might act as a potential neuroprotective agent against the cerebral ischemia-induced injury in rat brain through reducing lipid peroxides, scavenging free radicals, and improving the energy metabolism.

Seven known compounds, three diketopiperazine alkaloids, 12β-hydroxyverruculogen TR-2 (1), fumitremorgin C (2) and methylthiogliotoxin (5), two hetero-spirocyclic γ-lactam alkaloids, pseurotin A (3) and FD-838 (4), and cerevisterol (6) and herierin IV (7), were isolated from the mycelia of the basidiomycete Hericium erinaceum and identified by spectroscopic analyses. The antioxidant and antifungal activities of compounds 1-6 were evaluated. The results indicated that compounds 1, 3 and 6 exhibited potential antioxidant activity against DPPH (2, 2-diphenyl-1-picrylhydrazyl) radical with their IC50 data of ca. 12 μM, compared with positive control tertiary butylhydroquinone. In addition, compound 4 significantly inhibited the growth of two plant fungal pathogens Botrytis cinerea and Glomerella cingulata with an minimum inhibitory concentration of 6.25 μM for each, similar to that of the positive fungicide, carbendazim. Compounds 1-5 were isolated from the genus Hericium for the first time.

Direct γ-lactone formation via visible-light photoredox catalysis has been achieved efficiently including hydroxylalkylation of aromatic alkenes and transesterification. The present photocatalytic protocol has good regioselectivity and substrate compatibility, affording a novel way to intermolecular γ-lactone synthesis by the reaction of styrenes with α-bromo esters in the absence of any external oxidants.

In the novel title binuclear zinc(II) Schiff base complex, bis­(μ-11-thio­semicarbazonoindeno[1,2-b]quinoxaline-8-carboxylato)bis­[(dimethyl sulfoxide)zinc(II)] dimethyl sulfoxide tri­solvate, [Zn2(C17H9N5O2S)2(C2H6OS)2]·3C2H6OS, each ZnII atom is five-coordinated and situated in a distorted square-pyramidal environment, coordinated by two L2− ligands and one dimethyl sulfoxide mol­ecule. Each L2− ligand, which coordinates to two ZnII atoms, has two parts. One part, acting in a tridentate chelating mode, coordinates to one ZnII atom through two N atoms and one S atom, while another part coordinates to another ZnII atom through a monodentate carboxylate group. The whole complex has a dimeric structure. The coordination mode of the nearly planar L2− ligand is quite different from the most common mode for Schiff bases.

A new denitroaristolochic acid, demethylaristofolin C (1), together with six known alkaloids, crebanine N-oxide (2), (-)-sukhodianine-β-N-oxide (3), palmatine (4), corydalmine (5), dehydrocorydalmine (6), and corynoxidine (7), was isolated from the tubers of Stephania succifera. The structure of demethylaristofolin C was elucidated by spectroscopic techniques (UV, IR, 1D, and 2D NMR) and HR-ESI-MS analyses. These compounds exhibited antibacterial activities against Staphylococcus aureus and methicillin-resistant S. aureus strains in different degrees.

Corticotropin-releasing factor (CRF) is a neuropeptide that falls into the broad spectrum of having neurotransmitter/neurohormonal/neuromodulator activities. The design and synthesis of low molecular weight non-peptide antagonists for the CRF receptors is a very important area of research as they can be employed in the treatment of a wide variety of disorders. To investigate the ligand-receptor binding mode and design novel CRF1 antagonists, both quantitative and qualitative 3D-QSAR analysis have been performed on a data set of CRF(1) antagonists by using HypoGen and HipHopRefine programs of Catalyst software. The training set of HypoGen study included twenty-five structurally diverse CRF(1) antagonists with Ki values ranging from 0.5 nM to 10 microM. The common feature-based 3D-QSAR study used eight highly potent CRF(1) antagonists and four poor antagonistic ligands to generate 3D-pharmacophore models with excluded volumes. The obtained 3D-pharmacophore models from each study served as queries for virtual screening with a 'focused compound library' for novel CRF(1) antagonist development. Pharmacophore models obtained for antagonist binding are useful for CRF related chemical biology and drug design. Strategies and methods employed in this paper are simple and practical for medicinal chemists in drug R&D.

Three-dimensional pharmacophore models were generated for retinoid X receptor (RXR(gamma)) agonists using quantitative approach (CATALYST HypoRefine). One optimal pharmacophore model for selective RXR(gamma) agonists was determined through careful validation processes. The best quantitative model (Hypo-1) had five features and five excluded volumes: three hydrophobic aliphatic groups (HAL1, HAL2, and HAL3), one hydrophobic aromatic ring (HAR), and one hydrogen bond acceptor (HBA). The model was validated using a wide range of test molecules. It could predict agonist activity and identify highly potent molecules. The present results are valuable to discover and develop specific RXR(gamma) agonists with desired biological activities.

Thromboxane A(2) (TXA(2)) is an endogenous arachidonic acid derivative closely correlated to thrombosis and other cardiovascular diseases. The action of TXA(2) can be effectively inhibited with TXA(2) receptor antagonists (TXRAs). Previous studies have attempted to describe the interactions between the TXA(2) receptor and its ligands, but their conclusions are still controversial. In this study, ligand-based computational drug design is used as a new and effective way to investigate the structure-activity relationship of TXRAs. Three-dimensional pharmacophore models of TXRAs were built with HypoGenRefine and HipHop modules in CATALYST software. The optimal HypoGenRefine model was developed on the basis of 25 TXRAs. It consists of two hydrophobic groups, one aromatic ring, one hydrogen-bond acceptor and four excluded volumes. The optimal HipHop model contains two hydrophobic groups and two hydrogen-bond acceptors. These models describe the key structure-activity relationship of TXRAs, can predict their activities, and can thus be used to design novel antagonists.

Three-dimensional pharmacophore models were generated for A2A and A2B adenosine receptors (ARs) based on highly selective A2A and A2B antagonists using the Catalyst program. The best pharmacophore model for selective A2A antagonists (Hypo-A2A) was obtained through a careful validation process. Four features contained in Hypo-A2A (one ring aromatic feature (R), one positively ionizable feature (P), one hydrogen bond acceptor lipid feature (L), and one hydrophobic feature (H)) seem to be essential for antagonists in terms of binding activity and A2A AR selectivity. The best pharmacophore model for selective A2B antagonists (Hypo-A2B) was elaborated by modifying the Catalyst common features (HipHop) hypotheses generated from the selective A2B antagonists training set. Hypo-A2B also consists of four features: one ring aromatic feature (R), one hydrophobic aliphatic feature (Z), and two hydrogen bond acceptor lipid features (L). All features play an important role in A2B AR binding affinity and are essential for A2B selectivity. Both A2A and A2B pharmacophore models have been validated toward a wide set of test molecules containing structurally diverse selective antagonists of all AR subtypes. They are capable of identifying correspondingly high potent antagonists and differentiating antagonists between subtypes. The results of our study will act as a valuable tool for retrieving structurally diverse compounds with desired biological activities and designing novel selective adenosine receptor ligands.

Microdialysis coupled with RP-HPLC was used to study the blood pharmacokinetics of pingyangmycin hydrochloride in rabbits. Supelco RP-amide C16 column was adopted for the analysis of pingyangmycin hydrochloride. The data was analyzed with 3P87 program. The calibration curve was linear in the concentration range from 1.04 to 66.56 microg x mL(-1) (r2 = 0.999 4). The in vivo recovery of microdialysis probe was (42.8 +/- 3.4)% (n = 4). The concentration-time curve of pingyangmycin hydrochloride was fitted to two-compartment model. T1/2 alpha and T1/2 beta were 14.9 and 60.3 min, respectively. The method is proved to be accurate, simple and suitable for the pharmacokinetics study of pingyangmycin hydrochloride in rabbits.